Reservoir Regions Management with Unstructured Grid Reservoir Simuation Model

1. A method of managing a subsurface hydrocarbon producing reservoir having a plurality of wells, comprising the steps of: generating, using actual well trajectories of a plurality of wells in the reservoir, an unstructured grid model of the reservoir, the generating of the unstructured grid model of the reservoir comprising: determining a well dataset comprising, for each well of the plurality of wells of the subsurface hydrocarbon producing reservoir, well trajectory data defining a trajectory of the well; conducting, using the well trajectory data defining trajectories of the plurality of wells, a convex hull to determine a convex hull comprising a polygon that encloses the trajectories of the plurality of wells; determining, based on the convex hull, a reservoir region of the unstructured grid model of the reservoir, the reservoir region having a boundary defined by the polygon, wherein the unstructured grid model of the reservoir comprises a coarse grid size outside of the reservoir region and a fine grid size inside of the reservoir region; performing reservoir simulation of production of fluids from the reservoir based on the generated unstructured grid model; managing the reservoir based on the results of the performed reservoir simulation of production of fluids, the managing the reservoir comprising adjusting production of fluids from the reservoir.

2. The method of claim 1 , wherein the step of generating of the unstructured grid model of the reservoir using actual well trajectory of the plurality of wells in the reservoir is based on input data defining internal boundary geometry and internal boundary descriptions of the reservoir model, and on the well trajectory data and completion data obtained for the plurality of wells in the reservoir.

3. The method of claim 2 , wherein the unstructured grid model comprises a buffer region having an intermediate grid size, located between the fine grid size inside of the reservoir region and the coarse grid size outside of the reservoir region.

4. The method of claim 1 , wherein managing the reservoir comprises performing further development of the reservoir.

5. The method of claim 1 , wherein managing the reservoir comprises drilling a production well in the reservoir.

6. The method of claim 1 , wherein managing the reservoir comprises drilling an exploration well in the reservoir.

7. The method of claim 1 , wherein generating the unstructured grid comprises defining a buffer zone around the reservoir region, wherein unstructured grid model of the reservoir comprises an intermediate grid size in the buffer zone such that the unstructured grid model of the reservoir comprises an intermediate grid size between the fine grid size inside of the reservoir region and the coarse grid size outside of the reservoir region.

8. A data processing system for generating an unstructured grid model of a subsurface hydrocarbon producing reservoir with actual well trajectories of a plurality of wells of a subsurface reservoir during reservoir simulation, the generating of the model being based on input data defining internal boundary geometry and internal boundary descriptions of the reservoir model provided the data processing system, and on well trajectory and completion data for the plurality of wells in the reservoir obtained during drilling of the wells, the data processing system comprising: a memory receiving and storing the provided input data defining internal boundary geometry and internal boundary descriptions of the reservoir model; the memory further storing computer operable instructions causing the data processing system to generate the unstructured grid model with actual well trajectory of the plurality of wells during the reservoir simulation; a processor generating the unstructured grid model with actual well trajectory of the plurality of wells of the reservoir by performing in the under control of the stored computer operable instructions the steps of: receiving from the memory well perforation location coordinates of the plurality of wells in an unstructured grid model of the reservoir based on the well trajectory and completion data for the plurality of wells; forming a well dataset of well trajectory locations of the plurality of wells; conducting, using the well dataset, a convex hull to determine a convex hull comprising a polygon that encloses the well trajectory locations of the plurality of wells; transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir, the reservoir region having a boundary defined by the polygon, wherein the unstructured grid model of the reservoir comprises a coarse grid size outside of the reservoir region and a fine grid size inside of the reservoir region; and a reservoir simulator performing the reservoir simulation of production of fluids from the reservoir based on the generated unstructured grid model, wherein production of fluids from the reservoir is adjusted based on the results of the reservoir simulation of production of fluids from the reservoir.

9. The data processing system of claim 8 , further including a user display forming an output display of the results of the reservoir simulation of production of fluids from the reservoir based on the generated unstructured grid model.

10. The system of claim 8 , wherein transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir comprises defining a buffer zone around the reservoir region, wherein unstructured grid model of the reservoir comprises an intermediate grid size in the buffer zone such that the unstructured grid model of the reservoir comprises an intermediate grid size between the fine grid size inside of the reservoir region and the coarse grid size outside of the reservoir region.

11. A computer implemented method of generating an unstructured grid model of a subsurface hydrocarbon producing reservoir with actual well trajectories of a plurality of wells of a subsurface reservoir during reservoir simulation by a data processing system, the generating of the model being based on input data defining internal boundary geometry and internal boundary descriptions of the reservoir model provided the data processing system, and on well trajectory and completion data for the plurality of wells in the reservoir obtained during drilling of the plurality of wells, the data processing system comprising a memory, a processor, and a reservoir simulator, the method comprising the computer implemented steps of: receiving and storing in the memory the provided input data defining internal boundary geometry and internal boundary descriptions of the reservoir model; storing in the memory computer operable instructions causing the data processing system to generate the unstructured grid model with actual well trajectory of the plurality of wells during the reservoir simulation; generating in the processor the unstructured grid model with actual well trajectory of the plurality of wells of the reservoir by performing under control of the stored computer operable instructions the steps of: receiving from the memory well perforation location coordinates of the plurality of wells in an unstructured grid model of the reservoir based on the well trajectory and completion data for the plurality of wells; forming a well dataset of well trajectory locations of the plurality of wells; conducting, using the well dataset, a convex hull to determine convex hull comprising a polygon that encloses the well trajectory locations of the plurality of wells; transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir, the reservoir region having a boundary defined by the polygon, wherein the unstructured grid model of the reservoir comprises a coarse grid size outside of the reservoir region and a fine grid size inside of the reservoir region; and performing the reservoir simulation of production of fluids from the reservoir in the reservoir simulator based on the generated unstructured grid model, wherein production of fluids from the reservoir is adjusted based on the results of the reservoir simulation of production of fluids from the reservoir.

12. The computer implemented method of claim 11 , wherein the data processing system further comprises a user display and further including the computer implemented step of forming an output display of the results of the reservoir simulation of production of fluids from the reservoir based on the generated unstructured grid model.

13. The method of claim 11 , wherein transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir comprises defining a buffer zone around the reservoir region, wherein unstructured grid model of the reservoir comprises an intermediate grid size in the buffer zone such that the unstructured grid model of the reservoir comprises an intermediate grid size between the fine grid size inside of the reservoir region and the coarse grid size outside of the reservoir region.

14. A data storage device having stored in a non-transitory computer readable medium computer operable instructions for causing a data processing system comprising a processor, a reservoir simulator and a memory, to generate an unstructured grid model of a subsurface hydrocarbon producing reservoir with actual well trajectories of a plurality of wells of a subsurface reservoir during reservoir simulation, the generating of the model being based on input data defining internal boundary geometry and internal boundary descriptions of the reservoir model provided the data processing system, and on well trajectory and completion data for the plurality of wells in the reservoir obtained during drilling of the plurality of wells, the instructions stored in the data storage device causing the data processing system to perform the following steps: storing in the memory computer operable instructions causing the processor to generate the unstructured grid with actual well trajectory of the plurality of wells during the reservoir simulation; performing in the processor under control of the stored computer operable instructions the steps of: receiving from the memory well perforation location coordinates of the plurality of wells in an unstructured grid model of the reservoir based on the well trajectory and completion data for the plurality of wells; forming a well dataset of well trajectory locations of the plurality of wells in the reservoir; conducting, using the well dataset, a convex hull to determine a convex hull comprising a polygon that encloses the well trajectory locations of the plurality of wells; transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir, the reservoir region having a boundary defined by the polygon, wherein the unstructured grid model of the reservoir comprises a coarse grid size outside of the reservoir region and a fine grid size inside of the reservoir region, wherein production of fluids from the reservoir is adjusted based on the at least one reservoir region of the unstructured grid model of the subsurface reservoir.

15. The data storage device of claim 14 , wherein the data processing system further comprises a user display and the instructions further comprise instructions for forming an output display of the results of the reservoir simulation of production of fluids from the reservoir based on the generated unstructured grid model.

16. The device of claim 14 , wherein transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir comprises defining a buffer zone around the reservoir region, wherein unstructured grid model of the reservoir comprises an intermediate grid size in the buffer zone such that the unstructured grid model of the reservoir comprises an intermediate grid size between the fine grid size inside of the reservoir region and the coarse grid size outside of the reservoir region.

17. A method of generating an unstructured grid model with actual well trajectories of a plurality of wells of a subsurface reservoir during reservoir simulation by a reservoir simulator of a computer comprising a memory and a processor the generating of the model being based on input data defining internal boundary geometry and internal boundary descriptions of the reservoir model provided the computer, and on well trajectory and completion data for the plurality of wells in the reservoir obtained during drilling of the plurality of wells, the method comprising performing the computer implemented steps of: storing in the memory computer operable instructions causing the processor to generate the unstructured grid with actual well trajectory of at least one individual well during the reservoir simulation; performing in the processor under control of the stored computer operable instructions the steps of: receiving from the memory well perforation location coordinates of the plurality of wells in an unstructured grid model of the reservoir based on the well trajectory and completion data for the plurality of wells; forming a well dataset of well trajectory locations of the plurality of wells in the reservoir; conducting, using the well dataset, a convex hull to determine a convex hull comprising a polygon that encloses the well trajectory locations of the plurality of wells in the reservoir; transforming the convex hull into at least one reservoir region of the unstructured grid model of the plurality of wells of the subsurface reservoir, the reservoir region having a boundary defined by the polygon, wherein the unstructured grid model of the reservoir comprises a coarse grid size outside of the reservoir region and a fine grid size inside of the reservoir region, wherein production of fluids from the reservoir is adjusted based on the at least one reservoir region of the unstructured grid model of the subsurface reservoir.

18. The method of claim 17 , wherein transforming the convex hull into at least one reservoir region of the unstructured grid model of the subsurface reservoir comprises defining a buffer zone around the reservoir region, wherein unstructured grid model of the reservoir comprises an intermediate grid size in the buffer zone such that the unstructured grid model of the reservoir comprises an intermediate grid size between the fine grid size inside of the reservoir region and the coarse grid size outside of the reservoir region.